PLATE TECTONICS STUDY GUIDE
1. WHAT ARE THE 4 PIECES OF EVIDENCE FOR CONTINENTAL DRIFT?
Fossils, rock types, puzzle, ancient climates
2. WHICH 2 CONTINENTS ARE USED AS EVIDENCE FOR THE CONTINENTAL PUZZLE?
S. America and Africa
3. WHO WAS ALFRED WEGENER?
Person who proposed Pangaea and Continental Drift
4. WHAT IS THE NAME FOR THE SUPERCONTINENT?
Pangaea
5. WHY WAS THIS HYPOTHESIS REJECTED?
Couldn’t explain a force to move the plates
6. WHAT IS THE THEORY PLATE TECTONICS?
That the lithosphere is divided into plates and these plates move on the asthenosphere
7. WHERE DO EARTHQUAKES AND VOLCANOES MOST OFTEN OCCUR IN RELATIONSHIP TO PLATE TECTONICS?
Along plate boundaries
8. WHAT LAYER OF THE EARTH IS DIVIDED INTO PLATES?
Lithosphere (crust and portion of upper mantle)
9. WHAT MATERIAL IS THE CORE MADE OF?
Iron and nickel
10. WHAT IS THE THINNEST LAYER OF THE EARTH?
crust
11. WHAT IS THE ASTHENOSPHERE?
Portion of mantle that is fluid enough for the plates to float on
12. WHAT IS THE MOHO?
Boundary between upper mantle and lower mantle; discovered by earthquake waves (you do not need to know this for the test)
13. HOW DO SCIENTISTS DETERMINE THE INNER LAYERS OF EARTH?
Studying seismic waves
14. WHAT HAPPENS AT A SUBDUCTION ZONE?
More dense plate sinks below a less dense plate
15. WHAT IS A RIFT VALLEY? AT WHAT TYPE OF BOUNDARY WILL THIS OCCUR?
Middle of mid-ocean ridge where plates are spreading apart; divergent boundary
16. WHICH BOUNDARY CREATES EARTHQUAKES?
transform
17. WHAT FORMS ON THE OVERRIDING PLATE AT A SUBDUCTION ZONE?
volcanoes
18. WHERE THE 2 PLATES MEET AT AN OCEANIC-OCEANIC OR OCEANIC-CONTINENTAL BOUNDARY, WHAT FEATURE IS CREATED?
Volcanoes and trench
19. WHICH PLATE SUBDUCTS WHEN 2 OCEANIC PLATES CONVERGE?
More dense
20. AT A DIVERGENT BOUNDARY, WHAT ARE THE CHARACTERISTICS OF THE ROCKS FURTHEST FROM THE MID-OCEAN RIDGE?
Colder, older and denser
21. IDENTIFY THE MOTIONS FOR THE FOLLOWING BOUNDARIES:
a. CONVERGENT àß
b. DIVERGENT ßà
c. TRANSFORM
22. HOW DID THE HAWAIIAN ISLANDS FORM?
Hot Spot
23. WHY DOES MAGMA RISE TO THE SURFACE?
Less dense than surrounding material
24. WHAT ARE 3 THINGS THAT ARE FORMED AT A DIVERGENT BOUNDARY?
Mid-ocean ridge, rift valley, new seafloor
25. HOW DID THE ALEUTIAN ISLANDS FORM?
oceanic-oceanic convergent
26. NAME 3 MOUNTAIN CHAINS THAT FORMED BY CONTINENTAL-CONTINENTAL CONVERGENCE.
Himalayas, Appalachian, Rockies
27. WHAT CAN MINERALS IN ROCKS SHOW THAT PROVIDE EVIDENCE FOR PLATE TECTONICS?
Change in magnetic field of Earth
28. DESCRIBE THE 3 DIFFERENT EXPLANATIONS FOR THE MOVEMENT OF THE PLATES:
a. SLAB PULL- denser end of plate pulls the rest of the plate down toward the mantle
b. RIDGE PUSH- gravity pushes on the mid-ocean ridge, forcing the plates apart
c. MANTLE CONVECTION- heat from the core rises in the mantle and creates circular patterns affecting the plates above
29. What is the difference between magma and lava?
Magma is below earth’s surface, lava is above
30. Be able to label a diagram of the structure of a volcano- see packet
31. What is pyroclastic flow?
Movement of pyroclastic material (hot ash and rocks) down the side of a volcano
32. Where is the Ring of Fire?
around the Pacific Ocean
33. What type of volcano is the largest?
shield
34. What type of volcano has the most explosive eruptions?
Stratovolcano (or composite cone)
35. What are possible damages from earthquakes?
Building damage, fires, liquefaction, tsunami
36. Where is the epicenter located relative to the focus?
Above the focus
37. What is the elastic rebound hypothesis?
That rocks will rebound back to their original shape after an earthquake
38. What does the Richter scale measure?
Magnitude of the seismic waves
39. What fault is located in California?
San Andreas
40. How many seismic stations are needed to locate the epicenter of an earthquake?
3
41. What is a tsunami?
Wave generated due to displacement of land underwater
42. What is the difference between a seismogram and a seismograph?
Seismogram is the paper record from the seismograph- the instrument that measures earthquake activity
43. What type of fault results in the hanging wall moving below the footwall?
Normal
44. What type of fault results in the hanging wall moving above the footwall?
Reverse
45. What type of stress is involved in a transform fault?
Shearing
46. What is a contour line?
Line on a topo map that connects points of equal elevation
47. What is a contour interval?
Distance between adjacent contour lines
48. What do closely spaced contour lines indicate?
Steep slope
49. How can one determine the direction of streamflow?
V’s point upstream